# The card trick

I ask Jonathan to pick any 5 cards out of a deck with no Jokers.
He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Peter can't see any of this). I look at the cards and I pick 1 card out and give it back to Jonathan. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Peter. Peter looks at the 4 cards i gave him, and says out loud which card jonathan is holding (suit and number). How? (The solution uses logic, not sleight of hand)

Note by Joseph Chen
3 years ago

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I can only think that there is some information conveyed through the four cards. Perhaps there is some logic which implies that any 4 cards of the deck can represent any of the 52 cards in a standard deck somehow. But I cannot follow up with this idea.

- 2 years, 10 months ago